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Chemical Datasheet

NITRATING ACID, MIXTURE, (WITH <= 50% NITRIC ACID)

8 - Corrosive

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7697-37-2   (NITRIC ACID, ANHYDROUS)
  • 1796
  • Corrosive
none
NIOSH Pocket Guide International Chem Safety Card
none
  • NITRIC ACID
NFPA 704
Diamond Hazard Value Description
0
3 0
Blue Health 3 Can cause serious or permanent injury.
Red Flammability 0 Will not burn under typical fire conditions.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special
(NFPA, 2010)
General Description
A colorless to yellow or red liquid sometimes fuming reddish brown vapors (of nitrogen dioxide). Has a suffocating odor. Density 10.4 lb / gal. Typically contains 36% nitric acid and 61% sulfuric acid by mass (the rest is water). Corrosive to metals or tissue. Used for nitration reactions (in the manufacture of explosives and plastics).

Hazards

Reactivity Alerts
Air & Water Reactions
Water soluble with release of heat and fumes. Addition of acid to water causes spattering.
Fire Hazard
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. For UN1796, UN1826, UN2031 at high concentrations and for UN2032, these may act as oxidizers, also consult ERG Guide 140. Vapors may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.). Substance may react with water (some violently), releasing corrosive and/or toxic gases and runoff. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water. (ERG, 2016)
Health Hazard
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns or death. Reaction with water or moist air may release toxic, corrosive or flammable gases. Reaction with water may generate much heat that will increase the concentration of fumes in the air. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. (ERG, 2016)
Reactivity Profile
NITRATING ACID, MIXTURE, (WITH <= 50% NITRIC ACID) is a mixture of nitric with sulfuric acids. Reacts as a strong acid. Exothermically neutralizes all kinds of bases (including amines and amides). Acts as an oxidizing agent and a nitrating agent. May cause ignition in contact with alcohols, amines, ammonia, beryllium alkyls, boranes, dicyanogen, hydrazines, hydrocarbons, hydrogen, nitroalkanes, powdered metals, silanes, or thiols [Bretherick 1979. p.174]. May react violently with finely divided antimony [Pascal 10:504. 1931-34]. Reacts violently with bromine pentafluoride [Mellor 2, Supp. 1:172. 1956]. May react explosively with phosphine gas [Edin. Roy. Soc. 13:88. 1835]. An explosion occurs when nitric acid is brought into contact with phosphorus trichloride [Comp. Rend. 28:86]. Reacts exothermically with water to produce fumes and possible spattering.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

Response Recommendations

Isolation and Evacuation
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

As an immediate precautionary measure, isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2016)
Firefighting
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Note: Some foams will react with the material and release corrosive/toxic gases.

SMALL FIRE: CO2 (except for Cyanides), dry chemical, dry sand, alcohol-resistant foam.

LARGE FIRE: Water spray, fog or alcohol-resistant foam. Move containers from fire area if you can do it without risk. Use water spray or fog; do not use straight streams. Dike fire-control water for later disposal; do not scatter the material.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2016)
Non-Fire Response
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). All equipment used when handling the product must be grounded. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. A vapor-suppressing foam may be used to reduce vapors. DO NOT GET WATER INSIDE CONTAINERS. Use water spray to reduce vapors or divert vapor cloud drift. Avoid allowing water runoff to contact spilled material. Prevent entry into waterways, sewers, basements or confined areas.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. (ERG, 2016)
Protective Clothing
Excerpt from GUIDE 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer. It may provide little or no thermal protection. Structural firefighters' protective clothing provides limited protection in fire situations ONLY; it is not effective in spill situations where direct contact with the substance is possible. (ERG, 2016)
DuPont Tychem® Suit Fabrics
Normalized Breakthrough Times (in Minutes)
Chemical CAS Number State QS QC SL C3 TF TP BR RC TK RF
Nitric acid (50%) 7697-37-2 Liquid >480
Nitric acid (70%) 7697-37-2 Liquid 203 >480 >480 >480 140 >480 >480 >480 >480
Nitric acid (90%) 7697-37-2 Liquid >480 >480 >480 >480 >480
> indicates greater than.
A blank cell indicates the fabric has not been tested. The fabric may or may not offer barrier.

Special Warnings from DuPont

  1. Serged and bound seams are degraded by some hazardous liquid chemicals, such as strong acids, and should not be worn when these chemicals are present.
  2. CAUTION: This information is based upon technical data that DuPont believes to be reliable. It is subject to revision as additional knowledge and experience are gained. DuPont makes no guarantee of results and assumes no obligation or liability...

(DuPont, 2018)

First Aid
Excerpt from ERG Guide 157 [Substances - Toxic and/or Corrosive (Non-Combustible / Water-Sensitive)]:

Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or inhaled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. In case of contact with Hydrofluoric acid (UN1790), flush with large amounts of water. For skin contact, if calcium gluconate gel is available, rinse 5 minutes, then apply gel. Otherwise, continue rinsing until medical treatment is available. For eyes, flush with water or a saline solution for 15 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim calm and warm. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. (ERG, 2016)

Physical Properties

Chemical Formula:
  • HNO3 (nitric acid)
  • H2SO4 (sulfuric acid)
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: data unavailable
Molecular Weight: data unavailable
Water Solubility: data unavailable
Ionization Potential: data unavailable
IDLH: data unavailable

AEGLs (Acute Exposure Guideline Levels)

Final AEGLs for Nitric Acid (7697-37-2)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes 0.16 ppm 43 ppm 170 ppm
30 minutes 0.16 ppm 30 ppm 120 ppm
60 minutes 0.16 ppm 24 ppm 92 ppm
4 hours 0.16 ppm 6 ppm 23 ppm
8 hours 0.16 ppm 3 ppm 11 ppm
(NAC/NRC, 2017)

ERPGs (Emergency Response Planning Guidelines)

Chemical ERPG-1 ERPG-2 ERPG-3
Nitric Acid WFNA (7697-37-2) 1 ppm star-in-circle icon indicates that odor should be detectable near ERPG-1. 10 ppm 78 ppm
star-in-circle icon indicates that odor should be detectable near ERPG-1.
(AIHA, 2016)

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Nitric acid (7697-37-2) 0.16 ppm 24 ppm 92 ppm
(DOE, 2016)

Regulatory Information

EPA Consolidated List of Lists

Regulatory Name CAS Number/
313 Category Code
EPCRA 302
EHS TPQ
EPCRA 304
EHS RQ
CERCLA RQ EPCRA 313
TRI
RCRA
Code
CAA 112(r)
RMP TQ
Nitric acid 7697-37-2 1000 pounds 1000 pounds 1000 pounds 313
Nitric acid (conc 80% or greater) 7697-37-2 1000 pounds 1000 pounds 1000 pounds X 15000 pounds

(EPA List of Lists, 2015)

DHS Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Nitric acid 7697-37-2 80.00 % 15000 pounds toxic 68.00 % 400 pounds EXP/IEDP

(DHS, 2007)

OSHA Process Safety Management (PSM) Standard List

Chemical Name CAS Number Threshold Quantity (TQ)
Nitric Acid (94.5% by weight or greater) 7697-37-2 500 pounds

(OSHA, 2011)

Alternate Chemical Names